Process of precipitating organic substances in sulfite liquor.



PROCESS OF IPRECIJPITATING ORGANIC STTBS'IANCES IN SULFITE LIQUOR.

HANS Bnun LANDMARK. or Darwinian, NORWAY.

Patented Aug. 14, 1 917.

1,236,948. Specification of Letters Patent.

No Drawing Application filed December 7, 1916. Serial No. 135,694.

. To oZZ whom it may concern.

Be it known that I, Hans BRUN LAND- MARK, a subject of the King of Norway, re-

siding at Drammen, have invented certain 5 new and useful Improvements in Processes of Precipitating Organic Substances in Sulfite Liquor, of which the following is a specification.

As is well known sulfite liquor contains organic substances, the so called lignin substances, which are bound to sulfonic acids. In order to precipitate said organic substances the liquor may be heated under pressure with a stronger acid, for example, sulfuric acid, which causes thelignin sulfonic acids to be decomposed while S0 is being liberated. B a pressure of 6 to 7 atmospheres all 0 the organic substances comprised "under lignins are practically precipi-- 2o tatedl This process has howeverno practical value as the quantity of acid-at least 2% of the volume of the liquidwh1ch has to be added, is so large that the cost is quite out of proportion to the value of the organic substances precipitated.

Sulfite liquor contains free sulfurous acid which by oxidation Ina be converted into sulfuric acid. The sul uric acid thus produced decomposes an equivalent quantity of sulfonic acid bound to lignin substances, The hereby liberated sulfurous acid is further oxidized into sulfuric acid. which again decomposes fresh quantities of lignin sulfonic acid. This process is carried out according to a method invented by Strehlenert. According to saidimethod oxidation takes place by means of air or oxygen at a pressure of. about 20 atmospheres anda tempera-;

ture of about 200 C. Only at such a high 40 pressure and such a high temperature S0 is oxidized into 50,. therefore be maintained during the whole precipitating process, whereas the decomposition of the lignin sulfonic acid combinations, when suflicient acid is at hand,- takes place at 6 to 7 atmospheres.

Experiments show that it is possible to work, advantageously at this latter pressure, or that it is possible at this pressure to bring about oxidation. a

If for instance peroxid of hydrogen is introduced into an autoclave containing sulfite liquor at a pressure of 6 to 7 atmospheres the free sulfurous acid is oxidized and the above described precipitationis ob tained. By means of oxygen in reaction- Said condition must .acterized by decomposing the organic sulsparks in the presence of air or oxygen withable condition the S0 of the liquor may thus be oxidized to S0, at a pressure, which makes precipitation of the lignin substances possible at about 7 atmospheres.

The direct use of peroxid of hydrogen I7 would of course be too uneconomic. v My invention consists in a' new process V. consisting in that I produce the react ionable oxygen or active oxygen Within the autoclave itself, having previously placed the latter under a pressure of for instance i 7 atmospheres by pumpinginto it oxygen orair and then letting electric sparks pass through the gas. r i f A variation of the process consists in that I also introduce into'th aiitoclave" ozonized oxygen or ozonizedair at the pressure and temperature most favorable for the processv 5 Y 5 Having thus described the inventi I claim is':- a a 1. That process of precipitating organic substances in sulfite liquor, which is charac terized' by decomposing the organic sulfionic to acid compositions contained in said" liquor, {Q11 by means of a stronger acid; oxidizing the sulfurous acid by the discharge of electric .iil sparks in the presence of a suitable oxidizing medium; and maintaining the liquor under suitable pressure duringthe process.

2. The process of precipitating organic substances in. sulfite liquor, which is characterized by decomposing. the organic sulfonic acid combinations, contained in said liquor, so by means of sulfonic acid, produced by the oxidation of the SO, contained in said liquor, by the discharge of electric sparks in the presence of a suitable'oxidizing medium within the vessel in which the liquor is as under pressure, and inwhich the precipitation takes place.

3. The process of precipitating organic substances in sulfite liquor, which is charfonic acid combinations, contained in said liquor, by means of sulfuric acid, produced by the oxidation oi the SC) contained in the said liquor, by the discharge of electric in the vessel in which the liquor is under pressure, and in which the precipitation takes place.

fThe process of precipitating organic substances in sulfite-liquor, which is characterized by decomposing the organic sul fonic acid combinations, contained in said liquor, means of sulfuric 'ecid, produced In testimony whereof I- 'by the oxidation of theSO centained in the in presence of two witne said liquor, by the discharge of electric affix my signature sses.

sparks in'the presence of ozonized oxygen S'BRUN LANDMARK- 5 or ozonized air Within-the vessel in which Witnesses:

the liquor is under pressure, and in which Y'oii. NmLsE the precipitation takes place. E. Gxmumsom. A

It is hereby certified that in Letters Patent No. 1,236,948, grmtod August 1;, 1917, upon the application of Hm Bran Landmark, of Drenimen, Norway; for an improvement 'in Processes of Precipitat'mg Organic Substances in Sulfite Liquor, an error appears in the printed specification requiring correction as follows: Page :1, line 91, claim 2, for the word eulfom'c reed sulfuric; and that the said Letters Patent should be read with this correction therein that the some may conform to the record ofthe one in the Patent. Office.

Signed and sealed this 4th day of September, A. D. 1917.

[sun] R. -F. WHITEHEAD',

Aofiag Gomminiamr ofPdcnb. O1. 252. 

